Cinnamomum verum, called "true cinnamon tree" or Ceylon cinnamon tree is a small evergreen tree belonging to the family Lauraceae, native to Sri Lanka. Among other species, its inner bark is used to make cinnamon.

The old botanical synonym for the tree—Cinnamomum zeylanicum—is derived from Sri Lanka's former name, Ceylon. Sri Lanka still produces 80–90% of the world's supply of Cinnamomum verum, and it is also cultivated on a commercial scale in Seychelles and Madagascar.Cinnamomum verum trees are 10–15 metres (32.8–49.2 feet) tall. The leaves are ovate-oblong in shape, 7–18 cm (2.75–7.1 inches) long. The flowers, which are arranged in panicles, have a greenish color, and have a distinct odor. The fruit is a purple 1-cm drupe containing a single seed.

Cinnamomum cassia, called Chinese cassia or Chinese cinnamon, is an evergreen tree originating in southern China, and widely cultivated there and elsewhere in southern and eastern Asia (India, Indonesia, Laos, Malaysia, Taiwan, Thailand, and Vietnam).[2] It is one of several species of Cinnamomum used primarily for their aromatic bark, which is used as a spice. In the United States, Chinese cassia is the most common type of cinnamon used. The buds are also used as a spice, especially in India, and were once used by the ancient Romans.The tree grows to 10–15 m tall, with greyish bark and hard, elongated leaves that are 10–15 cm long and have a decidedly reddish colour when young.

Although related, cinnamon and cassia are not obtained the same plant. They should be treated as separate foods, both from a nutritional and a health standpoint. Scientifically speaking, there is only one true cinnamon, which is most commonly called "Ceylon cinnamon," and comes from the plant Cinnamomum zeylanicum. An alternative scientific name for Ceylon cinnamon is Cinnamomum verum, which simply translates as "true cinnamon."